Every month, more than 700 trucks rumble up and down the highways of Syria delivering food and other aid to hundreds of distribution points across the country. The trucks carry basic commodities such as rice, lentils, canned food, salt and cooking oil from the U.N.’s World Food Programme (WFP).

The WFP is working with more than two dozen organisations, including the Syrian Arab Red Crescent, the Agha Khan Foundation and 26 local charities. Together, they are helping millions of people stay alive in extremely challenging conditions. Some 4.25 million people inside Syria and another 1.5 million who have fled to neighbouring countries are receiving aid.

The scale of the operation is both impressive and depressing­, but it’s a lifeline that is at times hanging by a thread. During the summer, the WFP was forced to cut aid to a large number of Syrian refugees in Jordan and Lebanon. As a result, instead of an average of $27 per person per month, 211,000 refugees in Jordan are now receiving $14 a month, and 635,000 refugees in Lebanon receive $13.50. Not all refugees receive aid from the WFP, but these numbers represent a significant proportion of the total refugee population in the two countries. The UN's refugee agency, UNHCR, puts the number of Syrians seeking refuge in Lebanon at 1.1 million and in Jordan at around 630,000.

The cuts were needed so the organisation could focus on the even more vulnerable families within Syria amid a bleak funding outlook. The WFP needs $1.5 billion to fund its operations in Syria and for refugees in neighbouring countries this year. At the moment, it has a shortfall of $222 million for the final quarter of this year. Even if that gap is closed, the organisation will need to be cautious about restoring aid levels too quickly.

“Only if we receive enough funding to cover the first six months of 2016 would it be possible to re-include families who have been cut off from assistance and to restore the value of the voucher to its original average of $27 per person’, says Dina El-Kassaby, a spokeswoman for the WFP. “We want to avoid a situation where families are left in the lurch, not knowing if they will receive assistance in the coming months or get the depressing message that they have been cut off from assistance again. This has been a hand-to-mouth operation since its start, and this year has seen the worst levels of funding yet. It has taken its toll on hundreds of thousands of families.”

As fighting intensifies and continues to draw in more actors, the problems appear to be getting worse. When civil the war broke out in 2011, the WFP began offering food aid to 50,000 people. They are now helping more than 85 times as many.

The organisations might find it easier to cope if there weren’t also critical problems in other parts of the region. In Yemen, where another civil war rages, some 6.1 million people are severely food insecure. In Iraq, there are 8.2 million people in need of humanitarian assistance.

“Four out of the world’s 10 top countries with the highest stunting rates among children under 5 are Muslim countries”, says Abeer Etefa, another WFP spokeswoman. “Poverty and conflict exacerbate the problem. This year alone in Yemen, 1.8 million children are expected to suffer from some form of malnutrition. The humanitarian system is being stretched to [the] breaking point, with an unprecedented level of need in Syria, Iraq and Yemen.”